Fast blue dyeings on the fiber



Patented Sept. 20, 1932 UNET STES

HUGO SCHWEITZFR, OF WIESDORF-ON-THE-RHINE, GERMANY, ASSIGNOR TO GENERAL ANILINE WORKS, INC., OF NEW YORK, 'N. 'Y., A CORPORATION OF DELAWARE FAST BLUE DYEINGS ON THE FIBER No Drawing. Application filed February 7, 1928, Serial No. 252,687, and in Germany February 16, 1927.

The present invention relates to the production of fast blue dyeings on cotton fibers by treating with an aqueous copper compound solution cotton fiber which has been dyed with atrisazo dyestuff, containing an aromatic. amino-o-hydroxy=carboxylic acid compound, for example, amino salicylic acid, amino cresotinic acid or the like as the first component and a 2-amino-5-naphthol-7-sulfonic acid compound, e. g. 2-amino-5-naphthol-7-sulfonic acid or a derivative e. g. 2- phenylamino-5-naphthol-7-sulfonic acid as the end component.

In accordance with the invention clear blue shades are obtained by the said treatment on the fiber with aqueous copper compound solutions of dyestufis of the type aromatic-ohydroxy carboxylic acid-azo R -azo-R azo- R in which R and R signify naphthalene nuclei which may be substituted by sulfo-nic acid groups, the azo groups of which stand in para-position and R signifies the residue of a 2-a1nino-5-naphthol-7 -sulfonic acid compound. The shades are characterized by excellent fastness to washing in addition to such fastness to light. The process is moreover particularly valuable since this aftertreatment with copper compounds does not cause a change of shade.

The following example will illustrate my invention; without limiting it thereto.

Example 1.Cotton is introduced into a dye-bath, containing a solution of 2% of the dyestufi', salicylic acid-azo-l-naphthylamine- 'T- sulfonic acid azo l naphthylamine-azo-Q- obtained, possessing excellent fastness to washing and light.

The process proceeds in an analogous man ner by employing dyestuffs other than that described in the example, for example, such, in which the middle components are interchanged or in which both the middle components are a 1-naphthylamine-7- or fi-sulfonic acid, or in. which the first position is ccupied by a sulfonated para-amino-salicylic acid or an amino-cresotinic acid, or in which the end position is occupied by a derivative of Q-amino--naphthol-7-sulfonic acid, such as 2-phenylamino-5-naphthol-7- sulfonic acid and many others.

I claim 1. A process for the production of fast blue shades on cotton fibers which comprises treating with an aqueous copper compound solution cotton fibers which have been dyed with a trisazo dyestufi of the type aromatic-ohydroXy carboxylic acid-azo-R -azo-R -azo- R wherein R and R stand for naphthalene nuclei which may be substituted by sulfonic acid groups and to which azo groups are attached in para-position to each other and R stands for a 2-amino-5-naphthol-7-sulfonic acid residue, which may be substituted in the amino group by a radical of the benzene series.

2. A. process for the production of fast blue shades on cotton fibers which comprises treating with an aqueous copper sulfate so lution cotton fibers which have been dyed with a dyestuff having in its free state the probable formula:

amino-5-naphthol-7-sulfonicacid, to which of sodium sulfate have been added; dyeing is effected by boiling for an hour. The dyed goods are rinsed and treated with copper sulfate in the known manner, then rinsed again and soaped.

In this manner a beautiful blue shade is 3. As new products cotton fibers dyed and treated in accordance with claim 1.

4. As new products cotton fibers dyed and treated in accordance with claim 2.

In testimony whereof I have hereunto set my hand.

HUGO SCHWEITZER. 

